UV Index in August, United States

Last updated: May 3, 2025

As we step into August, understanding the UV Index in the United States becomes increasingly vital, especially for those residing in sunny areas. Awareness of UV levels is crucial for preventing sunburn and maintaining optimal skin health; even a brief exposure during peak hours can lead to harmful effects. In this month, when temperatures rise and sunlight graces us more intensely, typical UV exposure risks escalate, particularly around noon when the index peaks at 10. Armed with knowledge about UV levels, you can enjoy the warm summer days while protecting yourself against the sun's damaging rays.

Hourly UV Index in August

The UV Index throughout the day showcases a dynamic pattern of sun exposure, peaking during the afternoon. At 07:00, the index starts low at 1, gradually increasing as the sun rises. By 10:00, it reaches 6, signaling a rise in sun intensity, culminating in a striking 10 from 12:00 to 13:00, indicating a high risk of harm from unprotected sun exposure. As the day progresses, the UV Index declines, dropping to 3 by 17:00, and steadily returning to 1 by 19:00. This data highlights the importance of sun protection, especially during midday when the UV Index is at its highest.

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
Time	UVI	Category	Time to Burn
07:00	1	low	45 min
08:00	2	low	45 min
09:00	4	moderate	30 min
10:00	6	high	25 min
11:00	8	very high	15 min
12:00	10	very high	15 min
13:00	10	very high	15 min
14:00	9	very high	15 min
15:00	8	very high	15 min
16:00	5	moderate	30 min
17:00	3	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in August

As the seasons change, so does the UV Index, significantly impacting the risk of sunburn and the need for sun protection. The months of March through August see the highest UV levels, with March and April peaking at an index of 8, while May and June reach an extreme level of 11. Visitors and residents should be particularly cautious during June and July, when burn times drop to just 10 minutes at the extreme index. As we transition into fall, the UV intensity declines, with October still presenting a high index of 6, but moving to a moderate risk by November and December. It is advisable for everyone to wear protective clothing, seek shade, and use sunscreen during these high-risk months to minimize the risk of UV-related health issues.

Monthly Maximum UV Index for August, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in August. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.

Data source: Statistical UV Index data for August, based on information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

Compare August UV Index with Other United States Cities

The table above highlights how UV exposure in August compares to other major locations across United States. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.

August's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Chicago UVI	3	4	6	8	9	10	10	9	8	6	4	2
Brooklyn UVI	3	5	6	8	10	10	9	9	8	6	4	2
New York City UVI	3	5	6	8	10	10	9	9	8	6	4	2
August	3	5	8	8	10	11	11	10	9	6	4	3
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5